Magnetic brake



(N0 Model.)

0. S. WALKER. MAGNETIC BRAKE.

N20. 548,331. Patented Oct. 22,1895.

. IYR,

'NTTED STATES OAKLEY S. WALKER, OF woRoESTER, MASSACHUSETTS.

MAGNETIC BRAKE.

SPECIFICATION forming part of Letters Patent No. 548,331, dated October 22, 1895.

I Application filed February 20, 1895- Serial No. 539,155- 0 model.)

Worcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Improvement in Magnetic Brakes, of which the following is a specification, reference being had to the accompanying drawings, representing a magnetic brake embodying my invention and as applied to the periphery of a car-wheel.

Figure 1 represents a side elevation of a portion of the truck of a railway-car and showing two car-wheels in side view to which my invention is applied. Fig. 2 is a sectional view on line 2 2, Fig. 1. Fig. 3 is a side view of the brake-shoe and a portion of the car-wheel to which it is applied, the parts being shown on a larger scale than in Fig. 1. Fig. 4 represents the frictional surface of the brake-shoe. Fig. 5 represents the brake-shoe, showing the side opposite its frictional surface. Fig. 6 is a side view of the brake-shoe shown in sec tional view, the section being indicated by the broken line 6 6, Figl l. Fig. 7 is a transverse sectional view of the brake-shoe on line 7 7, Fig. 6. Fig. 8 is atop view of the bracket attached to the truck of the car, from which the brake-shoe is suspended; and Fig. 9 is a sectional view on line 9 9, Fig. 3, of one of the binding-posts upon the brake-shoe.

My invention relates to an improvement in electromagnetic brakes, and it has for its obj ect to provide a simple, cheaply-constructed, and more efficient electromagnetic brake by lessening the number of pieces and thereby avoiding joints and by reducing the length of the magnetic circuit.

Referring to the accompanying drawings, A denotes a portion of the framework of a car-truck, and B B the car-wheels.

Attached to the framework of the truck is a bracket 0, Fig. 8, its position being indicated by broken lines in Fig. 1.

Suspended from the bracket 0 and having a pivotal connection therewith is a bar D, to the lower end of which the brake-shoe E is attached by a bolt E.

The brake-shoe E consists of a cast-iron shell E cast in a single piece, inclosing a chamber F, in the center of which is a core G integral with the shell E The surface H of the brake-shoe is concave, having its curvature corresponding to the periphery or tread of the car-wheel and constituting the frictional surface of the brake- The frictional surface H of the brake-shoe is extended bymeans of wings I I, which project from the upper and lower sides of the shell E The chamber F is open upon the concave side H of the shoe to receive an electric coil J, which fills a portion of the chamber F, and the chamber is then'closed by the insertion of the blocks K, preferably of wood.

The back wall of the chamber F is provided with holes L L, and the electric coil J is so wound as to bring its ends M M opposite the holes L L, through which they are passed to binding-posts carried upon the shell E The binding-posts are formed by screwthreaded bolts N N, projecting from the shell E carrying collars N N, provided on their opposing surfaces with the semicircular recesses N N to receive the wires M M, and upon the opposite side of the bolts the collars are provided with similar semicircular recesses N N to receive the wires 0 and 0, one wire leading to the source of an electric current and the other being the return-wire.

Nuts P are carried upon the bolts N N in order to clamp the collars N N upon the wires interposed between them.

Between the collars N N and the shell E and also between the collars N N and the nuts P, I place washers P P of some nonconducting material, with the inner edges of the washers provided with flanges P extending intothe annular space between the collars and the bolts in order to insulate the collars.

The bar D, when the brake-shoe is in contact with the periphery of the wheel, is slightly inclined from avertical position, so the weight of the brake-shoe when non-magnetized will serve to carry it out of contact with the wheel, and in order to limit its motion when thus acted on by gravity and prevent it being carried too far from the wheel I provide a finger ICO R, adjustably attached to a bar S, supported by the framework of the truck, with the tip of the finger carried behind the brake-shoe and a short distance therefrom in order to serve as a stop for the brake-shoe.

YVhat I claim as my invention, and desire to secure by Letters Patent, is-- 1. In a magnetic brake, the combination of a shell provided with a bearing surface adapted to bear against a rotating Wheel and inclosing a chamber opening upon the bearing surface of said shell and provided with holes communicating with said chamber, a core inclosed concentrically in said chamber and integral with said shell, an electric coil held in said chamber and surrounding said core with its ends passing through the holes in the shell and a block of wood held in said chamber and covering said coil with its outer surface flush with the bearing surface of said shell, substantially as described.

2. In a magnetic brake, the combination with a framework and a rotating wheel, of a shell E having a concave surface forming a friction surface fitting the tread of the Wheel,

wings I, I, by which said friction surface is enlarged, a core G integral with said shell and forming a chamber F surrounding said core and opening upon the concave surface of said shell, an electric coil held in said chamber, a block of wood closing said chamber and covering said coil, a bar pivoted to said shell and to said framework, a bar S carried by said framework and a finger adjustably held on said bar, substantially as described.

In a magnetic brake, the combination of a shell E provided with a surface adapted to fit the periphery of a wheel, a core G and an annular chamber F inclosed in said shell, an electric coil held in said chamber and a binding post consisting of a bolt carried by said shell, a tightening nut on said bolt, a pair of collars provided with semicircular recesses to receive the wires and insulating Washers, substantially as described.

OAKLEY S. WALKER. Witnesses:

EMMA KESTER, RUFUS B. FOWLER. 

